Dimming and control arrangement and method for solid state lamps

Abstract

A system and method are disclosed for dimming light emitting diode (LED) lamps. A control unit is coupled to a dimmer and LED lamp. The dimmer receives power from an AC source and determines a phase angle of the AC power. The dimmer provides DC power to the lamp based on the phase angle. The control unit sends a control signal to the dimmer during a first portion of each half sine-wave of the received AC power. The control signal causes the dimmer to modify at least one function of the lamp. A plurality of LED lamps may be associated with a single dimmer, and the dimmer may individually instruct the lamps to modify their operational characteristics. The dimmer may send an operational signal back to the control unit. The operational signal may represent end of life information for the associated LED lamp. Other embodiments are described and claimed.

What is claimed is: 
     
       1. A system for dimming a light emitting diode (LED) lamp, comprising:
 an LED lamp, and 
 an LED dimmer coupled to the LED lamp, the LED dimmer configured to receive electrical power from an alternating current (AC) source, the LED dimmer comprising a processor and associated memory, the processor executing instructions for:
 determining a phase angle of said received AC power, 
 controlling direct current (DC) power to the LED lamp based on said determined phase angle, and 
 controlling a dimming range of the LED lamp in a range between a maximum brightness condition of the LED lamp and an off condition of the LED lamp; 
 
 wherein when the LED lamp is in the off condition the AC power source provides a constant minimum level of electrical power to circuit components of the LED dimmer and the LED lamp. 
 
     
     
       2. The system of  claim 1 , wherein the processor associated with the dimmer is configured to receive a control signal from a control unit during a first portion of each half sine-wave of the received AC power, the processor associated with the dimmer programmed to control an operating function of the LED lamp based on the control signal. 
     
     
       3. The system of  claim 1 , wherein the processor associated with the dimmer is configured to send an operational signal to the control unit during a portion of a half sine-wave of the AC power signal. 
     
     
       4. The system of  claim 2 , wherein the control signal comprises a voltage pulse. 
     
     
       5. The system of  claim 2 , the dimmer further comprising an LED power supply. 
     
     
       6. The system of  claim 2 , wherein the operational function comprises a color of light emitted by the LED lamp. 
     
     
       7. The system of  claim 2 , comprising a plurality of LED lamps coupled to the LED dimmer, and wherein the control signal includes address information associated with a selected one of said plurality of LED lamps, the processor associated with the dimmer programmed to control the LED dimmer to modify an operational characteristic of only said selected one of said LED lamps based on the control signal. 
     
     
       8. The system of  claim 1 , wherein the dimmer includes a processor with a memory coupled thereto, and the control unit includes a processor with a memory coupled thereto. 
     
     
       9. A method for controlling brightness of an LED lamp, comprising:
 receiving, at an LED dimmer, electrical power from an alternating current (AC) source; 
 determining, by a processor associated with the LED dimmer, a phase angle of said received AC power, and 
 at the processor, controlling the LED dimmer to provide power to the LED lamp to operate the LED lamp at a brightness based on the determined AC phase angle, wherein the brightness level is in a range between a maximum brightness condition of the LED lamp and an off condition of the LED lamp; 
 wherein when the LED lamp is in the off condition the AC power source provides a constant minimum level of electrical power to circuit components of the dimmer and the LED lamp. 
 
     
     
       10. The method of  claim 9 , wherein the received AC power comprises a duty cycle of from about 30-degrees to about 150 degrees of each half sine-wave of the AC source. 
     
     
       11. The method of  claim 9 , further comprising receiving a control signal at the dimmer during a first portion of each half sine-wave of the received AC power. 
     
     
       12. The method of  claim 11 , wherein the control signal comprises a voltage pulse impressed on a wire coupled to the dimmer. 
     
     
       13. The method of  claim 11 , wherein the processor instructs the dimmer to modify at least one operational characteristic of the LED lamp. 
     
     
       14. The method of  claim 13 , wherein the operational characteristic comprises a color of light emitted by the LED lamp. 
     
     
       15. The method of  claim 11 , wherein the control signal includes address information associated with one of a plurality of LED lamps, the method further comprising modifying an operational characteristic of only said one of said LED lamps based on the control signal. 
     
     
       16. The method of  claim 11 , further comprising sending an operational signal from the dimmer to a control unit during half sine-waves of the received AC power. 
     
     
       17. The method of  claim 16 , wherein the operational signal includes end of life information for the LED lamp. 
     
     
       18. A system for controlling a light emitting diode lamp for use in a system comprising an LED lamp connected to and in communication with a dimmer, and a non-transient machine readable storage medium encoded with a computer program code such that, when the computer program code is executed by a processor, the processor performs a method comprising:
 receiving, at the dimmer, electrical power from an alternating current (AC) source; 
 determining, at the processor, a phase angle of said received AC power, and 
 at the processor, controlling the dimmer to provide direct current (DC) power from the dimmer to an LED lamp, the DC power representative of a predetermined brightness of the LED lamp, the DC power based on the determined AC phase angle, wherein the predetermined brightness level is in a range between a maximum brightness condition of the LED lamp and an off condition of the LED lamp; 
 wherein when the LED lamp is in the off condition said AC power source provides sufficient power to the dimmer and the LED lamp to maintain a functionality of a circuit components of the dimmer and the LED lamp. 
 
     
     
       19. The system of  claim 18 , when the computer program code is executed by the processor, the processor further performs a method comprising receiving, at the processor associated with the dimmer, a control signal during a first portion of each half sine-wave of the received AC power. 
     
     
       20. The system of  claim 19 , wherein the control signal comprises a voltage pulse impressed on a wire coupled to the dimmer. 
     
     
       21. The system of  claim 19 , when the computing program code is executed by the processor, the processor further performs a method comprising modifying at least one operational function of said LED lamp based on the control signal. 
     
     
       22. The system of  claim 21 , wherein said operational function comprises a color of light emitted by the LED lamp. 
     
     
       23. The system of  claim 19 , wherein the control signal includes address information associated with a selected one of a plurality of LED lamps, when the computing program code is executed by the processor, the processor further performs a method comprising modifying an operational characteristic of only said selected one of said LED lamps based on the control signal. 
     
     
       24. The system of  claim 19 , further comprising sending, from the dimmer, an operational signal to a control unit during a second portion certain half sine-waves of the received AC power. 
     
     
       25. The system of  claim 18 , wherein the AC power source provides the received power to the dimmer so that the received AC power has a duty cycle of from about 30-degrees to about 150 degrees of each half sine-wave of the AC source.